Abstract: Comparing with traditional underwater acoustic system which just utilizes pressure information,combined-sensor system processes pressure and particle velocity information jointly in sound field.More information certainly brings nicer processing result.By using spatial directional information contained in combined-sensor,the Coherent Interference Energy Suppress (CIES for short) technology,which can effectively suppress coherent inference and detect linear spectrum signal and wide-band continuous-spectrum signal as well,is presented.Current research has shown inspiring result,and further research is going on.